1. Field of the Invention
The present invention relates to a scanning-laser microscope apparatus which detects transmitted light or reflected light from a specimen or fluorescence generated in the specimen when the specimen is scanned with a laser beam, and more particularly, to a light-amount detection unit for detecting the amount of light applied to a specimen for optical stimulation.
This application is based on Japanese Patent Application No. 2005-283023, the content of which is incorporated herein by reference.
2. Description of Related Art
A scanning-laser microscope is a microscope which irradiates a specimen with a laser beam while scanning it in the X-axis and Y-axis directions and which detects, using a detector, transmitted light or reflected light from the specimen or fluorescence generated in the specimen to obtain two-dimensional intensity information of the transmitted light, reflected light, or fluorescence. By associating this intensity information with the X-Y scanning position and displaying it on a display or the like as a two-dimensional intensity distribution, it is possible to observe a fluorescence image, a transmittance image, or a reflectance image of the specimen.
In such a scanning-laser microscope, a gas laser, such as an argon laser, is used. This gas laser exhibits variations in the output of the laser beam due to environmental changes, such as temperature changes. Therefore, even though the optical stimulus is to be quantified, quantification is difficult due to the variations in the irradiated laser beam.
To overcome this problem, Japanese Unexamined Patent Application, Publication No. 2003-195172 (hereinafter referred to as “Document 1”) discloses a method for stabilizing the laser light amount by monitoring the laser light intensity irradiated for observing a specimen and feeding back the monitored result to the laser light source. According to this method, it is possible to carry out quantitative observation in experiments such as time-lapse observation carried out over an extended period of time.
To quantify the optical stimulus when performing the optical stimulus experiment described above, it is essential to accurately determine the light amount of the stimulus light irradiating the specimen.
However, Document 1 does not discuss quantification of the stimulus.